Sodium 6-amino-4-hydroxy-5-[[2-(phenylsulphonyl)phenyl]azo]naphthalene-2-sulphonate

Endpoint summary

Description of key information

Not skin irritant

Not eye irritant

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin Irritation/Corrosion

Two studies are available that give information on the skin irritation/corrosion potential of the test substance.

In the key study the skin irritation test was performed to rabbit skin according to the Code of Federal Regulations" Title 16, Sections 1500.41". 0.5 g of the test item were applied to clipped and abraded skin of 6 rabbits. The duration of the application was 24 hours and the readings were performed after 1 and 48 hours and 7 days.

The purple colour of the test substance made the macroscopic examination of the erythema inaccurate at 1 hour-observation. The erythema and the oedema scores were calculated following the mean values after 24/48/72 h. For the scores at 48 h the greater value observed during the test was considered, as no observation was performed at this time-point. The erythema scores (mean values 24/48/72 hours) were 0.67 in four animals (animals #1,#3, #4 and #5), 1.33 in animal #2 and 0 in animal #6. The oedema scores (mean values 24/48/72 hours) were 0 in all animals.

In the supporting study the skin irritation test was performed to rabbit skin according to the OECD guideline 404.

The test substance was found to be not irritant when applied to clipped rabbit skin. The erythema scores were not possible to be assessed due to substance-related skin colour; after 8 days the erythema scores were 0 in all animals (mean values 24/48/72 hours). In two animals the oedema scores were 0 and in one rabbit was 0.33 (mean values 24/48/72 hours).

Eye Irritation/Corrosion

Two studies are available that give information on the eye irritation/corrosion potential of the test substance.

In the key study the substance was tested for eye irritation according to the guideline inserted into the "Code of Federal Regulations", Title 16, Section 1500.42. 100 mg of the test item were introduced into the right eye of six rabbits; the left eye served as a control. Evaluations were made by comparison with the control eye. The readings were made 1, 24, 48 hours and 4 and 7 days after the administration of the test substance.

In all animals the effects on the cornea, iris or conjunctiva were reversible within the 7 day-study period. The only two effects that were not reversible within the observation period were chemosis (grade 1 in animal #3) and iritis (grade 1 in animal #6). It should be noted that the eyes were not rinsed. Moreover, considering that the rest of the effects were reversible within the observation period, it could be expected that the latest effects will reverse within the 21 day-period (as reported in the CLP Regulation) instead of the 7 day-observation period. Only three animals out of six showed a mean score (24/48/72 h)≥1 for corneal opacity and for iritis (#2, #3, #4 and #2, #3, #6 respectively). All animals showed conjunctival erythema (redness) and oedema (swelling) (chemosis)mean values (24/48/72 h) < 2, except for one animal (#2: chemosis 2.33).

In the supporting study the eye irritation test was performed to rabbit eye according to the OECD guideline 405.

Mean values at 24, 48 and 72 hours for iris and corneal opacity were 0.00 in all three animals. The test item caused staining of conjunctivae in all animals at the 1-hour reading. The conjunctivae scores as mean values at 24, 48 and 72 hours were: in animals #1 and #2 redness 0.67 and chemosis 0.33; in animal #3 redness 1 and chemosis 1. All effects observed were fully reversible within the end of the study period.

The tests chosen as key studies have a known composition of the test substance while no information on the composition of the test item is available for the supporting studies.

Justification for classification or non-classification

SKIN IRRITATION/CORROSION

A corrosive substance is a substance that produces destruction of skin tissue, namely, visible necrosis through the epidermis and into the dermis, in at least 1 tested animal after exposure up to 4 hour duration.

Three subcategories are provided within the corrosive category 1:

Subcategory 1A where responses are noted following up to 3 minutes exposure and up to 1 hour observation;

Subcategory 1B where responses are described following exposure between 3 minutes and 1 hour and observations up to 14 days;

Subcategory 1C where responses occur after exposures between 1 hour and 4 hours and observations up to 14 days

To classify a substance as irritant, the major criterion is that at least 2 of 3 tested animals have a mean score of ≥ 2,3 - ≤ 4,0.

Category 2:

- Mean value of ≥ 2,3 - ≤ 4,0 for erythema/ eschar or for oedema in at least 2 of 3 tested animals from gradings at 24, 48 and 72 hours after patch removal or, if reactions are delayed, from grades on 3 consecutive days after the onset of skin reactions; or

- Inflammation that persists to the end of the observation period normally 14 days in at least 2 animals, particularly taking into account alopecia (limited area), hyperkeratosis, hyperplasia, and scaling; or

- In some cases where there is pronounced variability of response among animals, with very definite positive effects related to chemical eposure in a single animal but less than the criteria above.

 

EYE IRRITATION

Serious eye damage means the production of tissue damage in the eye, or serious physical decay of vision, following application of a test substance to the anterior surface of the eye, which is not fully reversible within 21 days of application.

Eye irritation means the production of changes in the eye following the application of test substance to the anterior surface of the eye, which are fully reversible within 21 days of application.

Irreversible effects on the eye (Category 1):

If, when applied to the eye of an animal, a substance produces:

- at least in one animal effects on the cornea, iris or conjunctiva that are not expected to reverse or have not fully reversed within an observation period of normally 21 days; and/ or

- at least in 2 of 3 tested animals, a positive response of corneal opacity ≥ 3 and/or iritis > 1,5 calculated as the mean scores following grading at 24, 48 and 72 hours after installation of the test material.

These observations include animals with grade 4 cornea lesions and other severe reactions (e.g., destruction of cornea) observed at any time during the test, as well as persistent corneal opacity, discoloration of the cornea by a dye substance, adhesion, pannus, and interference with the function of the iris or other effects that impair sight. In this context, persistent lesions are considered those which are not fully reversible within an observation period of normally 21 days. Substances are also classified in Category 1 if they fulfil the criteria of corneal opacity ≥ 3 or iritis > 1,5 detected in a Draize eye test with rabbits, recognising that such severe lesions usually do not reverse within a 21-day observation period.

The substance does not meet the requirements to be classified in Category 1.

Irritating to eyes (Category 2)

when applied to the eye of an animal, a substance produces:

- at least in 2 of 3 tested animals, a positive response of: corneal opacity ≥ 1 and/or iritis ≥ 1, and/or conjunctival redness ≥ 2 and/or conjunctival oedema (chemosis) ≥ 2

calculated as the mean scores following grading at 24, 48 and 72 hours after installation of the test material, and which fully reverses within an observation period of 21 days.

Based on the results obtained in the skin and eye irritation studies, the test substance does not need to be classified for skin and eye irritation according to the CLP Regulation (EC) No. 1272/2008.